Magento Product import/export module

I'm building a jewelry store and I need 'import/export from/to Excel' feature. Each of the products has about 20 custom options and multiple associated images so what I need is a module to allow transfering complete product data between Magento and Excel. The output file (csv, xml, xls - whatever works best) has to contain every single product parameter including all images and custom fields references, so I can edit everything directly from Excel and then run the module to update the inventory. Ideally the script will contain some basic error/data-structure checking to avoid DB corruption.